The invention relates to a coolant controller, in particular for a coolant circuit of an internal combustion engine. The coolant controller comprises: a thermostat valve arranged in a housing that comprises at least one valve closing member loadable by a working element as a function of a temperature value; a temperature sensor; as well as a heating element for the working element.
The invention further relates to a method for manufacturing such a coolant controller.
Cooling devices for an internal combustion engine, for example, in a motor vehicle, comprise in general a coolant controller with a thermostat valve that comprises a working element that operates as a function of the temperature of the coolant liquid. Such a cooling device with thermostat valve is disclosed in U.S. Pat. No. 5,482,010. In this connection, a working element is an expansion element that is provided with an additional heating device. Such coolant controller with thermostat valve controls flow of the coolant between the internal combustion engine and the radiator in such a way that during a warm-up phase the coolant coming from the internal combustion engine is essentially returned to the internal combustion engine without passing through the radiator by means of a bypass opening or a bypass line.
From a certain temperature level on during an operational phase, the coolant coming from the internal combustion engine is partially passed through the radiator and partially passed through the bypass opening in a mixed operation wherein the latter coolant portion is supplied to the internal combustion engine. Above a further preset temperature level, the entire coolant flow is passed through the radiator in order to provide satisfactory cooling of the internal combustion engine. For controlling the internal combustion engine and also for improving the coolant control, temperature sensors are utilized that are provided for detecting a parameter of a medium, preferably the temperature of the coolant. The sensors are provided with a cable that serves for transmission of the acquired data or the respective measured values to a processing unit such as a control device or an on-board computer.